Rhode Island Department of Education Lesson Plan Lesson Title: Bond Dissociation Energy and Resonance State Standards:(GLEs/GSEs) GSE - PS1 (9-11) - 4 National Standards: Context of Lesson: This lesson is after the class has done the strength of covalent bonds activity/lab in class. In that lab the students learned that triple bonds are stronger than double bonds which are stronger than single bonds. This class will focus on why knowing this is important. I will introduce bond dissociation energy to the class and relate it to the strength of bonds. I will also touch upon resonance which can also effect the bond dissociation energy. Opportunities to Learn: Depth of Knowledge: Prerequisite Knowledge: Plans for Differentiating Instruction: Accommodations and modifications: Environmental factors: Materials:
Objectives:
When given 3 compounds the students will be able to list them in order of decreasing bond dissociation energy.
Students will describe how oxygen atoms are bonded in ozone.
Instruction: Opening:
Talk about the lab from the day before.
Did the students see any trends in the lab?
Do they think there is any significance in the trends?
Engagement:
Bond dissociation energy.
What do you think this means?
Think about the lab and the trends we were just talking about...
Lead the students to define the word on their own and make the connections to the lab.
Its harder to break 3 rubber bands than 1 rubber band.
A triple bond is stronger and harder to break so it needs more energy to break it.
Why is it significant that it takes more energy to break a triple bond than a single bond?
What properties could that effect?
Melting and boiling points.
Do you think there are other things that can effect the bond dissociation energy?
Expect to hear “yes” because I asked the question.
There are other things that can effect bond strengths.
Resonance.
What is it?
Difficult to understand.
The electrons can move in order to stabilize a compound
Example: Ozone (O3)
It contributes to some exceptions to the octet rule.
As we already know chemistry is complicated and some rules can be broken.
Compounds with an odd number of valence electrons do not follow the octet rule and therefore have resonance.
Closure:
Review the trends that the students saw with bond dissociation energies.
Remind the students that the lab is due in the next class.
There will be a classroom activity on molecular orbitals in the next class, be prepared.
Assessment: The assessment for this class will be done through questioning and will be on the final unit test. Reflections: (only done after lesson is enacted) Student Work Sample 1 – Approaching Proficiency: Student Work Sample 2 – Proficient: Student Work Sample 3 – Exceeds Proficiency:
Lesson Plan
Lesson Title: Bond Dissociation Energy and Resonance
State Standards: (GLEs/GSEs)
GSE - PS1 (9-11) - 4
National Standards:
Context of Lesson:
This lesson is after the class has done the strength of covalent bonds activity/lab in class. In that lab the students learned that triple bonds are stronger than double bonds which are stronger than single bonds. This class will focus on why knowing this is important. I will introduce bond dissociation energy to the class and relate it to the strength of bonds. I will also touch upon resonance which can also effect the bond dissociation energy.
Opportunities to Learn:
Depth of Knowledge:
Prerequisite Knowledge:
Plans for Differentiating Instruction:
Accommodations and modifications:
Environmental factors:
Materials:
Objectives:
Instruction:
Opening:
Engagement:
Closure:
Assessment:
The assessment for this class will be done through questioning and will be on the final unit test.
Reflections:
(only done after lesson is enacted)
Student Work Sample 1 – Approaching Proficiency:
Student Work Sample 2 – Proficient:
Student Work Sample 3 – Exceeds Proficiency: